CASE STUDY

Trichoscypha hallei (Anacardiaceae)

Mohamed bin Zayed Project: Number 232531127

Participatory conservation of Trichoscypha hallei (Anacardiaceae), a threatened shrub classified as Endangered on the IUCN Red List, in the Akom II Forest, Southern Cameroon.

1. Introduction

Trichoscypha hallei is a shrubby plant belonging to the Anacardiaceae family. Its habitat in Cameroon is limited to the Akom II forest, located in the south of the country. However, it faces significant threats where environmental conditions are favorable for its development. Consequently, it is not widespread. These threats include slash-and-burn agriculture and deforestation for various purposes, which lead to habitat loss.

This project aims to contribute to the conservation of Trichoscypha hallei through several strategic actions:

• Establish a spatial distribution map of the species by conducting a thorough botanical inventory.

• Protect its habitat by using a participatory approach to seek sustainable alternatives to slash-and-burn agriculture.

• Contribute to increasing the species' population through appropriate generative propagation techniques.

2. Method

The method adopted is divided into two distinct phases: a preparatory phase and a field phase. However, we will not dwell on the preparatory phase.

• The Field Phase

Meeting with the People of Akom II

The study began with a meeting with the village chief of Akom II, whose collaboration fostered community involvement and enabled the provision of guides. This first step was followed by an interactive meeting with the residents, marking the launch of a participatory dialogue. Search for the Type Specimen of Trichoscypha hallei

The search consisted of locating the collection point of the paratype (Tinde van Andel 3917) in the forest pre-registered in the GPS. The point was previously identified using the GPS "Go To" function and compass, and the movement to reach these different points was done on foot through the forest.

Trichoscypha hallei Inventory and Mapping

At Mount Dangueng, eight 10,000 m² quadrats, oriented north-south, were defined, each subdivided into 16 subplots. Each subplot (25 m × 25 m) was inventoried individually. Each time a Trichoscypha hallei plant was encountered, it was georeferenced using a GPS (longitude and latitude) and its phenological status was recorded (sterile, flowering, fruiting). In each subplot, all observed individuals were identified by a botanist and counted. A botanical sample was also collected and pressed.

3. Results and Discussion

3.1. Results

Meeting with the population of Akom II.

The meeting with the village chief of Akom II was crucial for the study, facilitating collaboration and community buy-in. His support enabled effective mobilization, particularly through the recommendation of local guides. On December 3, 2023, an awareness-raising meeting brought together 25 participants, including community leaders, citizens, and administrators. A sample of Trichoscypha hallei was presented, highlighting its conservation status and ecological role. This exchange reinforced the participants' commitment to preserving the species and its habitat.

Search for the type specimen of Trichoscypha hallei

The collection site of the paratype was located, which allowed us to observe the growth of the type specimen and identify three additional georeferenced individuals. An experimental plot was then established around this subpopulation to test the most appropriate methodology, which would ensure accurate analysis and the development of better conservation strategies.

On Mount Dangueng, Trichoscypha hallei exhibits great variability in size, ranging from 4 to 27 meters in height, with diameters ranging from 4 to 18 cm. Its leaves are compound and its branches pubescent. Flowering is seasonal, with marked variability. Some individuals still bear flower buds. These buds appear on loose panicle inflorescences. In male flowers, the inflorescence can reach approximately 60 cm in length, while that of female flowers remains shorter. Fruiting begins between late July and early August, and the subglobose to ellipsoid fruits reach maturity in August in Cameroon, then turning a dark red. Inventory and mapping of Trichoscypha hallei

Of the ten (10) plots planned for the study, eight (8) were actually established, but only four (4) harbored individuals of the Trichoscypha hallei species. In total, 11 individuals were recorded, while six plots were found to be empty. Currently, the extent of occurrence of Trichoscypha hallei covers an estimated area of 4.26 hectares, or less than one square kilometer. However, a thorough inventory could refine this estimate. The low density in some areas makes data extrapolation difficult and underscores the importance of continuing inventories to establish a more realistic distribution map.

3.2. Discussion:

The funding delay, received after the fruiting period (May-August), prevented seed harvesting, which is essential for assisted regeneration. As a result, nursery establishment and seed sowing had to be postponed. The mismatch between funding availability and the seasonal cycle of Trichoscypha hallei thus compromised conservation activities. This species, whose regeneration is limited, faces unfavorable germination conditions due to high human activity. Its distribution area remains less than 1 km², classifying it as an endangered species. Conservation remains essential to limit its decline and ensure its survival.

4. Conclusion

The study on Mount Dangueng established the distribution area of Trichoscypha hallei at 4.26 hectares. Community participation in meetings is an encouraging sign of commitment. Inventories revealed a limited distribution of the species, with several empty plots. This highlights the need to conduct additional inventories to obtain a more precise estimate, while remaining cautious about extrapolations.